About this Image
At some 5,000 light years distant in the constellation of Sagittarius the beautiful emission Nebula M 17 is situated.
The Omega Nebula M17, also called the Swan Nebula, the Horseshoe Nebula, or (especially on the southern hemisphere) the Lobster Nebula,
is a region of star formation and shines by excited emission, caused by the higher energy radiation of young stars.
Unlike in many other emission nebulae, however, these stars are not obvious in optical images, but hidden in the nebula.
Star formation is either still active in this nebula, or ceased very recently. A small cluster of about 35 bright but obscurred stars seems to be imbedded in the nebulosity.
TEC-140 APO refractor with TEC flattener at f/7
|Camera||SBIG STL-11000M at -25C, internal filter wheel|
|Date||May 22, 2006.|
|Sky Conditions||mag 7, high transparency, temperature 15 C,|
Ha = 140 minutes (10 min sub-exposures),
Image aquisition, in Maxim DL 4.11; calibration and preprocessing in CCD-Stack;
Photoshop: curves, mild unsharp mask;
wavelet processing for brighter nebula parts;